Under a cloud, but living large. And apparently lucky in love -- again.

DrewPeterson: Do you feel in danger at all with me at all?

Chrissie: No.

DrewPeterson: We're happy.

He was the subject of a book -- and a storm of speculation. But tonight, Drew Peterson is behind bars .

Sue Doman: I hope I can go to the cemetery and tell my sister finally we got him. And I hope Drew Peterson rots in hell.

Charged with the murder of wife number three-- Kathy Savio -- facing up to 60 years in prison if he's convicted. His lawyer again this morning defending his client.

Brodsky: Every person who has been found not guilty has started off with an indictment. So an indictment is no indication of guilt whatsoever.

Tonight family and friends take you through the story of the marriage that is at the center of the new murder charges, and the disappearance of the young woman that started it all. You'll hear the results of lie detectors tests Peterson took about both women. And, in a never-before-seen interview, Drew Peterson defends himself in no uncertain terms and denies -- again -- any involvement in Kathy's death -- or Stacy's disappearance.

Hoda Kotb: Are you a good con?

DrewPeterson: I believe I can be, yeah. But I'm not conning anybody about this.

Hoda Kotb: How does one know when you're conning and when you're not, if you're good at it?

DrewPeterson: I guess you don't. I guess you don't.

Even so – when we spoke late last year, Peterson sounded like a man who was prepared for the worst.

DrewPeterson: I'm not gonna run anywhere. I'm gonna face it head on and have my legal team fight it.

It wasn't supposed to end this way. Especially not for Drew Peterson. As a boy, he dreamed of becoming a cop. And after a stint in the Army -- with the military police -- he made good on his dream. Peterson joined the force in the Chicago suburb of Bolingbrook in the late 1970's. He went on to become an undercover narcotics officer. But his work took a toll at home. By the early 1990's, drew Peterson had been married twice and had two sons.

Hoda Kotb: Why do you keep getting married again?

DrewPeterson: I-- I-- I don't want to be alone. I want to be with somebody. I want somebody to love me.

In 1992 -- after wives number one and two -- that new "somebody' was Kathy Savio. Drew met her on a blind date.

DrewPeterson: Another policeman's wife fixed ups up. She was a lot of fun. We did things we liked. We went to shows and stuff.

Kathy was in her late twenties, working as an accountant. She told her sister, Sue Doman, that the Bolingbrook police officer was a great guy.

Sue Doman: He would -- horrible, swearing names. B*tch, whore. "You look like a dog". She needed to go to Jenny Craig. She needed to do anything to make herself look better 'cause she was lookin' horrible.

Sue says there was violence too -- she says Kathy told her she was beaten. Hospital records show Kathy landed in an emergency room on one occasion -- and the records reflect the story Kathy told her sister.

Sue Doman: He took her head, and -- took her hair, she had long hair and he beat her against a wooden table. He was angry at her.

Hoda Kotb: What kind of injuries did she sustain?

Sue Doman: She had a laceration on her head. She became dazed. She had black and blue marks all over her.

DrewPeterson: That never happened.

Hoda Kotb: Okay.

DrewPeterson: I say, if you ever had the opportunity to meet Kathy Savio -- she would not be somebody that would sit there and let somebody take and grab her hair and beat it against a wooden table. Kathleen Savio was a hell cat. And you didn't mess with her. Ever.

DrewPeterson: I don't know if she did or she didn't. I think that might have been -- Kathleen was constantly trying to build a case against me for a possible divorce.

In late 2001, Kathy received an anonymous letter that shattered her world. It said her husband was having an affair. She confronted Drew. Her sister Sue happened to call right after.

Sue Doman: I heard yelling. He said, "Hang up on that b*tch." And he slammed the phone down. She called me back and she said, "I'm on my way to get an order of protection." She said, "Drew threw me against the refrigerator. He was chasing me with a stick." And I said "What's -- going on?" She said, "I got an anonymous letter. Someone from the police department said I was the laughing stock of the town.” He was having an affair. And he said it wasn't true.

But it was true. And what made it even harder for Kathy to bear was that the new woman in her husband's life was a teenager -- a 17-year-old barely out of high-school. Kathy decided to file for divorce. And some months later she filed for something else -- an order of protection from her husband.

Hoda Kotb: There was a quote in it. And the quote from your sister was "He wants me dead."

After Kathy Savio received an anonymous letter in late 2001 telling her about Drew's affair with a teenager, she filed for divorce. Sue Doman is Kathy's sister.

Sue Doman: She was sad because she was losing her husband. But she was happy in a roundabout way because now she was able to live her life and be free. Not be battered, not be mentally abused.

A few months later, Drew and his young girlfriend, Stacy Cales, moved into a new home just blocks from his old house. He and Kathy were still arguing fiercely. Drew's friend and former neighbor Steve Carcerano saw a couple of ugly spats.

Steve Carcerano: Kathy was always angry with Drew when Stacy came into play. She would be complaining about the age thing a lot. And you know I even pulled her aside a couple of times and said, "It doesn't really matter about the age Kathy, whether she's 18 or whether she's 28 or 42. You know, he found somebody else."

But Kathy told Sue that Drew and his girlfriend would deliberately antagonize her.

Hoda Kotb: How often did they-- did Stacy and Drew do drive-bys?

Sue Doman: All the time. They actually could have gone a different way to get out of the-- out of the-- subdivision, but they would do that constantly.

Hoda Kotb: They went by, what, honk the horn or did what?

Sue Doman: Yeah. They would honk the-- honk the horn or-- or kinda like pull in the driveway and back up. All the time. Callin' her names.

The Bolingbrook police, drew's fellow officers, were called to Kathy's home at least 17 times over a two-year period for cases that involved Drew. Some were custody disputes. Twice Kathy was charged with battery -- and twice she was found not guilty. Once she reported a violent -- even menacing -- act: in July 2002, she told police, Drew surprised her in the house and threatened her with a knife.

Sue Doman: She was coming downstairs with a clothes basket to do clothes. And he was dressed up in a S.W.A.T. uniform. He grabbed her and held a knife to her throat. He was really mad.

Sue Doman: That he had to pay so much money of child support. He was angry. He was going to kill ‘er. And she said "You know I thought -- I would never see my boys again. I -- I thought I would never see them again."

Hoda Kotb: She was that terrified huh?

Sue Doman: Yes.

Hoda Kotb: So.

Sue Doman: And she told him "You go ahead and kill me. You just go ahead and do that now."

Kathy said Drew put the knife away and left. And Kathy later filed a police report about the incident. But she said she didn't want to get Drew arrested and she declined to get another order of protection. Drew, for his part, denied the whole thing and was never charged. He also denied ever deliberately antagonizing Kathy.

Sue Doman: He convinced everyone and anyone that she was absolutely crazy, mentally ill.

Sue says that all along, Kathy was telling her family that she was afraid of Drew -- deathly afraid.

Sue Doman: She told me she felt she was not going to make it. He was gonna kill her, and it was gonna look like an accident.

By March 1, 2004, Drew and Kathy's divorce had come through, although the financial settlement was pending. About 9 that night, Steve Carcerano was returning home from work.

SteveCarcerano: And Drew happened to come down the street. And pulled up next to me in his squad car. And he thinks something might be wrong because he's been trying to drop off the kids for the past day and a half, and that's not like Kathy not to be there when the kids were being dropped off.

Drew had a locksmith open the door to the house - he says nobody had a key. He asked Steve and another neighbor, Mary, to go upstairs and look for Kathy. But -- odd as it seems -- he didn't go up with them.

Hoda Kotb: Why didn't you just sort of bust in and try to find out what was going on with her

DrewPeterson: ‘Cause Kathleen would have tried to accuse me of doin' something or stealin' something from her. That's just the way she was.

Steve says he will never forget what he saw.

SteveCarcerano: When I looked towards the back of the bathroom. There was a balloon-type object. And as I walked closer to it, it was Kathy laying there naked.

Mary started screaming. Drew came running up.

Hoda Kotb: What did you see?

DrewPeterson: She was in a dry bathtub. And I believe I remember her laying face down and her hair was wet. But I don't remember any blood-soaked hair or anything like that.

Hoda Kotb: Cause the, I think the initial police report mentions there was a gash on her --

SteveCarcerano: What Drew immediately did upon entering the bathroom is he checked her pulse. And then he started screaming out, "What am I gonna tell my children? What am I gonna tell my children?" And very distraught. You know I looked right into his eyes. And he got very emotional, very quickly. And he called the police department.

The Bolingbrook force handed the investigation over to the Illinois state police. But as he waited for the autopsy results, even a loyal friend like Steve Carcerano had some questions about drew's role.

SteveCarcerano: You get mixed feelings right away. You know, he is a police officer. They were going through a-- you know, a very-- battling divorce.

But weeks later, a coroner's jury ruled Kathy's death an accident -- death by drowning -- despite the facts that didn't seem to fit: an empty bathtub. Bruises that had been discovered on Kathy's body.

Hoda Kotb: When they originally-- called that an accident, did you think they were right on with that-- with that? Did you think that was the right call?

DrewPeterson: Well, I wasn't made privy to a lot of things. So it's just like when everything came out, everything sounded like it was an accident.

Hoda Kotb: But h-- I-- I mean, I'm a novice. I don't know. But it seems like a dry bathtub with no water in it and--

DrewPeterson: Well the-- the-- the police did a-- a test on the tub and they filled the tub up. And they guessed there was a leak, or there was a leak in the drain. And it took, like, two hours for the tub to drain dry.

The conclusion was enough for Carcerano.

SteveCarcerano: When the coroner's report came back, again, you know, I felt satisfied with that. Obviously they're professionals. They know what they're doing.

Four years later, there would be a second coroner's report. This one would tell a very different story about how Kathy Savio died. But by then, Drew Peterson was used to living under a cloud of suspicion -- used to a white hot media storm of questions -- about what happened to not just one wife -- but two.

By the time his third wife, Kathy, was found dead in a bathtub in March 2004, Drew Peterson had already moved on. The latest love of his life was a teenager named Stacy Cales.

Hoda Kotb: What-- what-- what's the thing, if you had to put your finger on the thing you-- you loved the most about her, what is it?

DrewPeterson: She had a warm, giving demeanor about her all the time. All the time.

When Drew and Stacy started their affair, he was a 47-year-old police sergeant. Stacy, a high-school graduate, was just 17 -- 30 years his junior.

Hoda Kotb: I know people said, "What's going on there?"

DrewPeterson: Sure.

But, Peterson says, he squared the age gap with Stacy.

DrewPeterson: I said, "Do you mind that I'm 47?" And she goes, "Do you mind that I'm 17?" just like, kinda like a weird feeling. But I -- she was beautiful . And it was exciting having a young, beautiful woman interested in me. And I pursued the relationship.

And, he says, Stacy did too.

DrewPeterson: Every time I tried to get out of the relationship, she would pursue me. Leaving little roses and notes on my car and stuff. So it was exciting. So --

Kerry Simmons: I know he had bought her a car. Furnished the apartment. And it was -- you know, a lot of things that she didn't have.

Hoda Kotb: So the relationship started. She was like a kid, I mean, in a way. Just very naive.

DrewPeterson: Well she was very mature for her age in a lot of senses because she had a very tough upbringing.

Stacy Ann Cales was the third of five children born to Anthony and Christie Cales. Two siblings died young. Court records show that Stacy's mom was in and out of trouble with the law. Her mother took off for good in 1998 and her dad began moving the family around the country. Pam Bosco was close to the family -- and Stacy.

PamBosco: Oh, she was a darling. Bubbly warm caretaker you know. Just very very very sweet. Very much a family girl.

A family girl -- who wanted one of her own.

PamBosco: It's her closeness and her willingness to get close I think that made her available, probably, to an older person. She was just-- she was looking for something like that, you know, the warmth-- the-- maybe the possibility that could bring a family to her.

Her family says she fell hard for Drew Peterson. He fell hard too.

SteveCarcerano: When he met Stacy, it seemed like he had a glow in his eye. He seemed very happy with her. You know, she's young. She's attractive. He seemed happy with her.

But Stacy's family was not glowing. Just the opposite -- they told her to run -- not walk -- from the new guy in her life.

Kerry Simmons: We were just, "You're nuts. You're crazy. This guy is well over 30 years older than you. He still has a wife and you should not be involved with this guy".

DrewPeterson: Kathy and I were going through a divorce. But we were still living in the same house. And I was living in the basement of the house, and Kathy was living upstairs. And we still saw the children. We still had meals together and stuff. But there was no romantic contact between us.

Stacy eventually married Drew. They had two children together and took in Drew's sons with Kathy. Stacy seemed to be living her dream. By all accounts, he was a good dad and she was an awesome mom.

Kerry Simmons: Never saw her upset with those kids. I mean she -- she loved those kids so much. Those were like -- they were her life. And I think she really wanted to five those kids the life that she felt she didn't have. or the opportunities that she didn't have growing up.

She did birthday parties, marshmallow roasts, backyard barbeques. Any excuse for a family get-together. Any excuse for fun with the kids.

In October 2007, her youngest, lacy -- then two -- was supposed to go trick-or-treating for the first time.

PamBosco: She was so looking forward to having Lacy get dressed up and actually walk around the block and particiapte with Halloween.

It never happened. Three days before Halloween, Stacy Peterson's husband told the world that Stacy had run away. Vanished. Stunned, stressed, Stacy's family and friends told the police that something was terribly wrong.

Kerry Simmons: She would never leave those kids. Absolutely not. She took those kids everywhere with her.

In October 2007, when Kathy Savio's family learned that Drew Peterson's wife Stacy had disappeared, they drew an immediate conclusion.

Hoda Kotb: When you learned that Stacy, his fourth wife, had gone missing, what did you think?

Her family and friends suspected foul play and organized dozens of searches.

Cassandra: Touches my heart to see everybody out here. you know, showing that they care and that they're here to help.

Drew Peterson did not join in -- he told anyone who'd listen that they were looking in the wrong place.

Drew Peterson: I'd be looking on a beach.

Hoda Kotb: You think she ran off with someone and is just enjoying herself on a beach somewhere?

Drew Peterson: I believe that. But I'm guessing.

Stacy's family never bought that story. Instead they urged the Illinois State Police to focus on the Bolingbrook police sergeant -- and the state of the Peterson marriage.

Stacy and Drew had been married barely four years when she vanished. Her step-sister Kerry Simmons says early on, they seemed to be doing well.

Kerry Simmons: They looked happy, they acted happy and they looked, you know, they looked fine.

But Kerry says, slowly, surely the Petersons' marriage unraveled. She blames the 30-year age gap.

Kerry Simmons: I think he just started to wonder more and more every day that, you know, Stacy was going to leave him.

In what sounded like a replay of drew's marriage to Kathy, Stacy's family and friends told investigators the two seemed to be battling constantly. That Stacy said Drew would abuse her verbally, criticize her so severely that she felt insecure about her looks and had several plastic surgeries.

PamBosco: Just putdown kind of stuff and just very demeaning things. That's why she just went out and had these cosmetic things done to her body.

And that wasn't all. In other stories similar to those Kathy told her family years earlier, Kerry says Stacy confided that Drew got physical with her too.

Kerry Simmons: He threw her down the stairs. There was an instance where he had knocked her into the TV. I think one time he actually picked her up and threw her across the room. I mean she's small. She's 100 pounds.

Drew for his part insisted he never got physical with either woman. But he did draw his own parallels between both wives. Not flattering ones.

HodaKotb: You said of-- of your wife Stacy that she had some mental instability. And you said of your wife Kathy, she was irrational. I don't--

DrewPeterson: Both-- both--

HodaKotb: I don't get it.

DrewPeterson: Both these girls had very much troubled youth. And they all had emotional problems.

Kerry says she begged Stacy to leave drew when she heard about the violence at home.

Kerry Simmons: The only thing I could tell her was "You need to get out. You know, we can get a truck, help you move, pack your stuff up and get you out of there in a matter of hours".

But she says Stacy was paralyzed by fear.

Kerry Simmons: She felt that if she left that house and took those kids, he would come after her.

Drew worked as a night watch supervisor for the Bolingbrook police. Neighbor Sharon Bychowski says he would check in at home like clockwork throughout his shift.

Sharon: So he would go in at 5 o'clock, he would do his roll call, he'd come back. He would eat here in uniform, then he'd go back out on the beat. He'd stay an hour or so. Come back.

Those close to Stacy say the constant checks did not end there. They told investigators Drew would actually follow his wife in his car when she went out.

Kerry Simmons: She went to breakfast with one of the other sisters and he would circle the parking lot to make sure that she was only in there with her other sister. And not a guy.

Family and friends say when Drew wasn't following her by car, he was tracking her by phone.

Sharon: We went to get our hair cut and he called her eight times. He was always there.

At one point, Pam says, Stacy made a startling discovery in her husband's briefcase.

PamBosco: There was her phone record completely written and documented where she was. Who the phone call was to. Stuff like that.

Sharon: So she went out and got herself a new cell phone and gave me the bag to hold "Here, I don't want Drew to know I have this. The box because it has the sim card information and things he could use to track my calls again."

In September 2006, Stacy was devastated when half-sister Tina died of colon cancer. Those who know her well says Tina's death may have spurred her to take stock of her three-year-old marriage.

Sharon: She was really struggling to end the marriage. She really wanted to move out or have Drew move out. She wanted the end of that process. She wanted it over with.

But while Stacy's family portrayed it as a marriage gone bad, drew insisted he loved his wife, denied that they were arguing constantly and furthermore drew says he did not track his wife by car or cell, didn't keep close tabs on her at all. Otherwise he says, she wouldn't have had relationships with other men.

DrewPeterson: I mean she wanted a boob job, I got 'er a boob job. She wanted a tummy tuck, she got that. She wanted braces, lasik surgery, hair removal. Anything -- Stacy loved male attention. And we did all these repairs on her, she wanted it, she got it.

HodaKotb: Uh huh.

DrewPeterson: And we did all these repairs on 'er.

Sharon: He bought her a motorcycle to ask her if it would buy him three more months with her.

But in the days leading up to her disappearance, friends say Stacy Peterson was more determined than ever to leave the marriage.

After Stacy Peterson vanished in October 2007, the family home came under siege.

DrewPeterson: I can stand here and cry if that would make you happy. I'm doing the best I can with a hard situation. The best I can.

But as the weeks went by, Drew Peterson's "best" began to look like his "worst".

DrewPeterson: Watch this...I am not the typical person I am. I'm normally I am a lot more humorous like that.

Kathy Savio's family watched his antics with growing disgust.

HodaKotb: So, Sue, you-- you've seen Drew on TV. What do you think when you watch him on the screen?

Sue Doman: My heart beats real fast. I get mad. I just want to-- just to tear right into him. And say, "Do-- how could you sit there so calmly? You have no feelings. You-- you make me sick.

While Drew bantered, investigators were searching the woods and waterways around the Peterson home. They came up empty-handed. As the months passed, they've had little to say publicly about their investigation. This is what we know about Stacy's last days from her friends and family.

On Wednesday, Oct. 17, eleven days before Stacy disappeared, a friend says he got an e-mail from her. It was the eve of her fourth wedding anniversary. This is what the e-mail said.

I am finding that the relationship I am in is controlling, manipulative and somewhat abusive.

That same day, Stacy left a phone message for her dad.

StacyPeterson: Hey Dad, it's me, ah, Stacy. I just wanted to call you and tell you I love you. I also wanted to give you my new phone number. OK, love you.

Pam told investigators that Stacy had reached a decision -- she was ready to file for divorce.

Pam Bosco: She was going to look for a lawyer.

Saturday, Oct. 27. The day before Stacy went missing. Pam says Stacy's sister Cassandra went to the peterson home for dinner.

Pam Bosco: She said Stacy leaned forward and gave her a hug and said "I love you", if anything happens to me, he killed me. It wasn't an accident."

Sunday, Oct. 28. The day Stacy vanished. Her family and friends say she was supposed to help paint a house that day. They told investigators the last contact with her was about 10 that morning when a friend called to talk about the plans.

Pam Bosco: He said, "Where are you?" "I'm in bed yet," she said. "I'm still in bed." And she hadn't gotten up yet to paint this house they were planning on painting that day.

Drew for his part, had always publicly declined to give a detailed account of his activities the day Stacy disappeared -- until recently.

Now, his version of events during those critical hours.

He says he got home from his overnight shift at the Bolingbrook police department between 5:30 and 6 a.m. That's when he saw Stacy for the last time.

Drew Peterson: We were talking about what she was gonna do that day. And she was explaining to me she was gonna run errands for -- with her grandfather, for her grandfather.

Hoda Kotb: So there wasn't a whole lot of --

Drew Peterson: No. She was waking up. I was tired. That type of thing.

He dismissed a report, attributed to one of his sons, that the two had argued.

Drew Peterson: There was no argument or anything that morning. I talked to my children about that. And they don't recall any type of fight. They were sleeping.

Drew says he went to sleep -- only to be awakened by the children between 10 and 11 that morning. By then he says Stacy was gone. He says he called in sick to work -- then spent the day playing with the kids, running errands and taking the family out to dinner.

Hoda Kotb: How come there was no communication between the two of you on that day?

Drew Peterson: She was going through a period where she said she wanted her space. So I just gave her her space that day

But he says Stacy finally did call -- at 9 pm -- to tell him she'd found someone else and was leaving him -- and that the car was parked at a nearby airport.

Hoda Kotb: And then you went out looking for her. And you wound up, according to phone records, by the Chicago area shipping canal.

Drew Peterson: There was an individual that lives close by there that I thought she might have been romantic with and I was driving through there.

By now Stacy's family was really worried --they hadn't heard from her all day. Pam says Stacy's sister Cassandra started phoning her in the afternoon -- but the phone was off.

Pam Bosco: And Cassandra could not get through on that cell phone to Stacy.

Finally around 11:30 that night, Cassandra called Drew.

Pam Bosco: That's when she heard the rustling of the keys. He's out of breath -- that kind of stuff. And she--he said that "she's left me. She went with another man. She went to the Bahamas or something. She took her bikini. The passport's missing and she took money."

Drew says there was nothing mysterious going on -- he'd finished looking for Stacy and was back in his own driveway when he took the call.

Days after she vanished, state police called Stacy's disappearance "a potential homicide" and named a suspect: drew. Almost immediately, investigators began taking a long hard look at his past. And they focused on Kathy Savio's death. Was it really -- as the coroner's jury had decided -- an accident?

Glasgow: With 29 years of experience, there was not doubt in my mind, it wasn't an accident. That was clear.

It was a stunning announcement from the will county state's attorney, who was not in office when Kathy died -- he said her death would be re-investigated. Her body exhumed and autopsied again.

Sue Doman: I was thinking, "Thank God". Thank God because now you're looking at it again.

Four months later -- the coroner made it official. As speculation about his role grew, Drew Peterson -- who'd quit his job as a cop -- seemed to behave more and more outlandishly. And he found a new love -- 24-year-old Christina Raines said she was ready to become the fifth Mrs. Peterson.

ChristinaRaines: I don't believe that he did anything wrong. And well, I love him. I have a lot of fun with him. And we get along good.

But maybe not good enough. The engagement was on then off, then on again. It's not clear where things stand now.

For the last year and a half, Peterson has been father and mother to four kids -- his two sons with Kathy, both now in their teens, and the young son and daughter he had with Stacy.

Drew Peterson: The little ones, they’re not sure. They're not talking about it much anymore. The older two, they just deal with it. They're pretty much consumed in their school activities.

When we visited the Peterson house late last year, pictures of Stacy were everywhere. Her clothes still hung in the closet. And Drew was still telling anyone who asked that she was living out her life somewhere else -- probably on a beach.. If she is, she's along way from the jail where Drew Peterson now sits.

More than 18 months after Stacy Peterson disappeared -- and five years after Kathy Savio's body was discovered -- Drew Peterson made his first court appearance today.

The flamboyant former police sergeant was in a jaunty mood joking with reporters about his spiffy outfit.

Drew Peterson: "3 squares a day and this spiffy outfit, how could I beat that. And this look at this bling, my God."

But Peterson will have to wait until later this month to answer charges that he drowned Kathy in a bathtub. Will County State's attorney James Glasgow.

JamesGlasgow: The grand jury returned a 2-count bill of indictment today, charging 2 counts of first-degree murder, one on the theory of intentionally killing, the second on knowingly doing an act that can cause great bodily harm.

Bond was set at an astonishing $20 million.

JamesGlasgow: I felt that this was as grave and serious a case as I've ever handled.

Peterson's arrest was welcome news to Kathy's family.

Henry Savio: When I found out he was under arrest, it was probably the best day in the world. I was ready to open a bottle of champagne.

A trial is likely many months away but when it does happen, prosecutors are counting on a new state law that could allow witnesses like Kathy's sister to testify about things they say she told them.

Sue Doman: She told me He was gonna kill her and it was gonna look like an accident.

JamesGlasgow: What you're basically allowing the victim of a violent crime to do is to testify from the grave.

Drew Peterson has always maintained that he could not be Kathy's killer because he was with his family when she died. Peterson attorney Joel Brodsky said this morning on the today show that his client has nothing to fear because he's not guilty.

JoelBrodsky: Drew has accounted for all his time during the period of time that Kathleen died. He, the scenario of him doing this is basically almost impossible for him to accomplish.

Author Derek Armstrong--who says he spent well over 100 hours interviewing Drew Peterson--says he would be skeptical about anything the ex-cop said.

The author says as he listened to Peterson's stories about his early career as an undercover cop, what struck him was: the man can act.

Derek Armstrong: He's proud of all these things you know, when he talks about how he can con people and fool people and so on. He actually used the word "con". It's not my language.

Peterson not only talked extensively to Armstong for his book, he also agreed to take polygraph tests. Could he con his way through them? Peterson told us, "No way".

Hoda Kotb: Seemed like it would be not difficult to figure out how to maneuver.

DrewPeterson: I think if you talk to the polygraph op-- operator, they might have a little different story than-- than a policeman having the ability to-- beat a lie detector test.

So what did the test reveal about Kathy's murder? There were four questions, among them, this one: did you have any involvement in the death of your ex-wife Kathy in 2004? Peterson answered no. He was found to be not deceptive on that question -- and all the others about her.

Hoda Kotb: Were you surprised that everything blew through like that?

DrewPeterson: No I was not. I was answering truthfully.

But how truthful was it? Armstrong says Peterson's attorney decided which topics could be addressed and which were off-limits. So Peterson, he says, knew what was coming.

Derek Armstrong: Yes, he was prepared for the questions.

Armstrong says there were other questions he wanted answered -- which were rejected by Peterson's attorney.

Derek Armstrong: The key one would be did he hire someone or know of someone being hired to -- to harm either Kathleen Savio or Stacy Peterson. I wasn't allowed to ask that question.

JoelBrodsky: Didn't have anything to do with the questions.

For his part, Drew's attorneydenies he put limits on the questions and says he advised his client not to take the tests.

JoelBrodsky: In my personal opinion it’s like a flip of a coin. It just wouldn't do him any good.

Drew also took a polygraph about Stacy's disappearance. There were six questions in all. Peterson was found to be not deceptive on three, including whether or not he physically harmed Stacy in any way during the time of her disappearance. He answered no to that question. But his answers were deceptive on the other three.

Hoda Kotb: The first one was, "Did you last see Stacy at home when you got home from work?" You answered, "Yes." The test showed that you were being deceptive. Were you surprised when the test showed that?

Drew Peterson: Yes. That's-- I answered truthfully.

Hoda Kotb: Okay, next question, "Do you know the whereaboutsof your wife?" You answered, "No." The test showed you were being deceptive.

Drew Peterson: Right.

Hoda Kotb: Again--

Drew Peterson: No, I didn't--

Hoda Kotb: --any explanation?

Drew Peterson: None. None.

Hoda Kotb: "Did you receive a phone call on October 28th, 2007, from your wife telling you that she was leaving you?" You answered, "Yes." The test showed you were being deceptive. I mean, what is the deal here? All these-- these three questions seem like pretty big questions. And each one showed, according this test, you were being deceptive. Right?

For more than a year, as investigators reviewed the evidence, the country has speculated about drew petersons involvement in Stacy's disappearance and Kathy's death… Kathy's sister has no doubt about the role he played.

Sue Doman: I-- I believe that he had something to do with my sister's death. And I believe that something happened with Stacy. And he thought since he got away with it the first time, let's do it again.

But Drew also has his supporters-- even female fans.

Hoda Kotb: These are e-mails or letters or whatever you've gotten. "You won't have trouble findin' a woman. I wish it was me."

Here's another one. "Here's my number. Call me any time." You've gotten-- you have a smile. You've gotten over a 100 phone numbers, love notes and all that kind of stuff. What's that like?

Drew Peterson: It's flattering.

Nothing seems to rattle Drew Peterson. Not the suspicions of others. And not the tough questions about the two wives he's lost.

Drew Peterson: And I have no way to prove to you that I'm not. So all I can do is tell you the truth that I'm not.

There is one heartbreaking truth. Drew's four children with Kathy and Stacy are motherless. They're staying with drew's grown son. But with Drew Peterson possibly facing a long prison term ... They could spend years without a father as well.

As for the rest of Stacy's family and friends, drew's arrest is a huge relief

Pam: We're just happy for the Savio family. We always said that Stacy and Kathleen had one thing in common and that was Drew Peterson.

And they're not giving up hope that Stacy's case will be resolved. One day.

Pam: So I believe in the end, we'll eventually find Stacy and bring her home.

Dateline wires the home of a volunteer, Jenny, from top to bottom with hidden cameras. Then she called repairmen to her house for a simple problem we created as a test with Jenny's pool. NBC's Chris Hansen reports.